The following description relates to a vane pump seal and, more particularly, to a vane pump seal with a single seal tube that incorporated an internal O-ring and has backup rings on each end.
In a pump system of an engine or transmission of an aircraft, for example, first and second vane pump elements are provided for operation about a rotor. Each vane pump typically has two labyrinth seals that seal the spinning rotor to limit leakage from a high pressure region surrounding the rotor outer diameter to a low pressure region surrounding the rotor inner diameter. The labyrinth seals provide for a very tight clearance between stationary seals and the spinning rotor and this tight clearance limits the potential for leakage to occur.
The tight clearance can lead to issues, however, arising from thermal growth, misalignment or axial movement of the components noted above or from the occurrence of small contamination particles passing through fuel filters and causing various parts to touch and which can result in galling. These and other issues can lead to seizure of either of both of the labyrinth seals and a seized labyrinth seal can be a source of significant leakage as well as a loss of pump efficiency.